I have found that every Niger I've had at some point goes through a period of adolescent aggression. Doesn't matter how much you feed them, no matter what you feed them. They especially like to suddenly turn on clownfish and chase them down. They will pursue much larger fish like a full grown Diamond Goby or anyone else that isn't a fast swimmer.
IMO if you can get past the adolescent stage that lasts 6-8 months, the more mature Niger will again focus on their regular food sources. Which many comments above are right about that needing to be a meatier diet that's targeted for carnivores. Those fangs are not there just for show.
I should add that Nigers are not "tamed" by a full belly. It's predator curiosity pure and simple. You can feed them until they are about to pop and they will still chase that one fish, kill it and leave the bulk of the carcass for you.
IMO if you can get past the adolescent stage that lasts 6-8 months, the more mature Niger will again focus on their regular food sources. Which many comments above are right about that needing to be a meatier diet that's targeted for carnivores. Those fangs are not there just for show.
I should add that Nigers are not "tamed" by a full belly. It's predator curiosity pure and simple. You can feed them until they are about to pop and they will still chase that one fish, kill it and leave the bulk of the carcass for you.